package com.atguigu.facade;

public class Screen {

	private static Screen instance = new Screen();
	
	private Screen() {
		
	}
	
	public static Screen getInstance() {
		return instance;
	}
	
	public void up() {
		System.out.println("Screen up");
	}
	
	public void down() {
		System.out.println("Screen down");
	}
}
